<!DOCTYPE html>
<html>
<style>
    #container {
        position: relative;
        width: 400px;
        height: 400px;
    }
    #container > div {
        position: absolute;
        width: 100%;
        height: 100%;
    }
    #background {
        background-image: linear-gradient(red, orange);
        filter: invert(1);
    }
    #foreground {
        color: purple;
    }
</style>
<div id="container">
    <div id="background"></div>
    <div id="foreground">This text should be purple on a background with a light blue gradient.</div>
</div>
</html>
